Many alarm detection systems have visual display means, frequently termed annunciators, for indicating the respective locations of detectors which have transmitted alarm signals. Generally, this is done by illuminating a bulb behind a portion of the annunciator display, where the bulb position is related (either by location, the information on the panel in front of the bulb, or some other means) to the location of the alarmed detector. The detectors can sense various alarm-type events, such as window breakage, unauthorized door opening, unauthorized presence in a given physical space, presence of products of combustion, and so forth. Thus when a fire starts and the battalion chief or other official in charge of men and equipment arrives at the fire scene, if the structure has an annunciator panel he can generally tell at a glance which detectors have been alarmed and thus the general extent of the fire at that time.
A shortcoming of present annunciator technology is that the display evident to the arriving fire fighters does not indicate how the fire spread; that is, it does not depict the origin, the direction of spread, or the speed at which the fire progressed. For example, if the fire is spreading five times more rapidly in one direction than another, it is extremely helpful to know this. Further, it is important to know where the fire started, both for bringing the blaze under control and for a subsequent possible arson investigation. Accordingly, it would be most helpful if the arriving supervisor could simply push a button on the annunciator and have it recreate the entire sequence of annunciator panel illumination, but at a rate much faster than the actual rate at which the detectors were alarmed. It is, of course, important that the recreation of the panel information be provided at a rate related to the time differences between successive detector alarms. The present invention is particularly directed to the provision of such an information handling system, particularly suitable with fire and other alarm detection systems.